Automation often replaces human labor, but very rarely in the last sixty years has it eliminated an entire occupation. Only one of the 270 detailed occupations listed in the 1950 US Census has since been eliminated by automation, according to a working paper by Harvard economist James Bessen. The one exception: elevator operator.

While the government has removed other occupations from the Census due to factors like lack of demand (boardinghouse keepers) and technological obsolescence (telegraph operators), only elevator operators owe their occupation’s demise mostly to automation, Bessen found.